[refactoring] update ast structure of "Parameter", "Class", "FunctionCall", "MethodCall", "New" and "StaticCall" nodes

pkg/ast/visitor/dump.go

@@ -203,18 +203,6 @@ func (v *Dump) Nullable(n *ast.Nullable) {
 	v.printNode(n.GetNode())
 }
 
-func (v *Dump) Reference(n *ast.Reference) {
-	v.printIndentIfNotSingle(v.indent - 1)
-	v.print("&ast.Reference{\n")
-	v.printNode(n.GetNode())
-}
-
-func (v *Dump) Variadic(n *ast.Variadic) {
-	v.printIndentIfNotSingle(v.indent - 1)
-	v.print("&ast.Variadic{\n")
-	v.printNode(n.GetNode())
-}
-
 func (v *Dump) Parameter(n *ast.Parameter) {
 	v.printIndent(v.indent - 1)
 	v.print("&ast.Parameter{\n")

pkg/ast/visitor/null.go

@@ -30,14 +30,6 @@ func (v *Null) Nullable(_ *ast.Nullable) {
 	// do nothing
 }
 
-func (v *Null) Reference(_ *ast.Reference) {
-	// do nothing
-}
-
-func (v *Null) Variadic(_ *ast.Variadic) {
-	// do nothing
-}
-
 func (v *Null) Parameter(_ *ast.Parameter) {
 	// do nothing
 }